logger: Downgrade some warning messages

A warning implies something went wrong and (possibly) the user should do
something about it. However, warnings are not always used this way.

For example:

* When a fallback value for a `${..}` reference is used, this shouldn't
  produce a warning (or notice) since using fallbacks is not something
  bad.
* pulse telling you that it uses the default sink because no sink was
  specified also does not warrant a warning (even notice may be too
  high).
* Whenever polybar shuts down it produces a "Termination signal
  received..." warning. Since there isn't a more proper way to shut down
  polybar, it should not produce a warning. Same argument for a
  `screenchange-reload`

include/components/config.hpp

@@ -335,7 +335,7 @@ class config {
       return convert<T>(move(value));
     } catch (const xresource_error& err) {
       if (has_fallback) {
-        m_log.warn("%s, using defined fallback value \"%s\"", err.what(), fallback);
+        m_log.info("%s, using defined fallback value \"%s\"", err.what(), fallback);
         return convert<T>(move(fallback));
       }
       throw value_error(sstream() << err.what() << " (no fallback set)");
@@ -364,7 +364,7 @@ class config {
       m_log.info("File reference \"%s\" found", var);
       return convert<T>(string_util::trim(file_util::contents(var), '\n'));
     } else if (has_fallback) {
-      m_log.warn("File reference \"%s\" not found, using defined fallback value \"%s\"", var, fallback);
+      m_log.info("File reference \"%s\" not found, using defined fallback value \"%s\"", var, fallback);
       return convert<T>(move(fallback));
     } else {
       throw value_error(sstream() << "The file \"" << var << "\" does not exist (no fallback set)");

include/modules/meta/base.inl

@@ -68,7 +68,7 @@ namespace modules {
   template <typename Impl>
   void module<Impl>::halt(string error_message) {
     m_log.err("%s: %s", name(), error_message);
-    m_log.warn("Stopping '%s'...", name());
+    m_log.notice("Stopping '%s'...", name());
     stop();
   }
 

src/adapters/pulseaudio.cpp

@@ -59,7 +59,7 @@ pulseaudio::pulseaudio(const logger& logger, string&& sink_name, bool max_volume
     // get the sink index
     op = pa_context_get_sink_info_by_name(m_context, DEFAULT_SINK, sink_info_callback, this);
     wait_loop(op, m_mainloop);
-    m_log.warn("pulseaudio: using default sink %s", s_name);
+    m_log.notice("pulseaudio: using default sink %s", s_name);
   } else {
     m_log.trace("pulseaudio: using sink %s", s_name);
   }
@@ -134,7 +134,7 @@ int pulseaudio::process_events() {
         o = pa_context_get_sink_info_by_name(m_context, DEFAULT_SINK, sink_info_callback, this);
         wait_loop(o, m_mainloop);
         if (spec_s_name != s_name)
-          m_log.warn("pulseaudio: using default sink %s", s_name);
+          m_log.notice("pulseaudio: using default sink %s", s_name);
         break;
       default:
         break;
@@ -189,7 +189,7 @@ void pulseaudio::inc_volume(int delta_perc) {
       // avoid rounding errors and set to m_max_volume directly
       pa_cvolume_scale(&cv, m_max_volume);
     } else {
-      m_log.warn("pulseaudio: maximum volume reached");
+      m_log.notice("pulseaudio: maximum volume reached");
     }
   } else
     pa_cvolume_dec(&cv, vol);

src/components/controller.cpp

@@ -173,7 +173,7 @@ bool controller::run(bool writeback, string snapshot_dst) {
     m_event_thread.join();
   }
 
-  m_log.warn("Termination signal received, shutting down...");
+  m_log.notice("Termination signal received, shutting down...");
 
   return !g_reload;
 }

src/components/screen.cpp

@@ -107,7 +107,7 @@ void screen::handle(const evt::randr_screen_change_notify& evt) {
   }
 
   if (changed) {
-    m_log.warn("randr_screen_change_notify (%ux%u)... reloading", evt->width, evt->height);
+    m_log.notice("randr_screen_change_notify (%ux%u)... reloading", evt->width, evt->height);
     m_sig.emit(exit_reload{});
     m_sigraised = true;
   }

src/modules/bspwm.cpp

@@ -148,7 +148,7 @@ namespace modules {
 
   bool bspwm_module::has_event() {
     if (m_subscriber->poll(POLLHUP, 0)) {
-      m_log.warn("%s: Reconnecting to socket...", name());
+      m_log.notice("%s: Reconnecting to socket...", name());
       m_subscriber = bspwm_util::make_subscriber();
     }
     return m_subscriber->peek(1);

src/x11/tray_manager.cpp

@@ -916,7 +916,7 @@ void tray_manager::handle(const evt::client_message& evt) {
   if (!m_activated) {
     return;
   } else if (evt->type == WM_PROTOCOLS && evt->data.data32[0] == WM_DELETE_WINDOW && evt->window == m_tray) {
-    m_log.warn("Received WM_DELETE");
+    m_log.notice("Received WM_DELETE");
     m_tray = 0;
     deactivate();
   } else if (evt->type == _NET_SYSTEM_TRAY_OPCODE && evt->format == 32) {